Sarah Nader - snader@shawmedia.com
Patti Whelan of McHenry participates in a tai chi exercise class at Family Alliancein Woodstock on Thursday, March 21, 2013. The number of people afflicted with Alzheimer's disease is expected to reach 13.8 million by 2050, millions more than previously anticipated, according to a new study in the journal Neurology. Exercise is known to help slow the effects of Alzheimer's.